The wait program

Interface

wait reads a list of pids in a
(possibly empty) block,
and unquotes it.

wait waits for every child whose pid is
listed in pids.... If pids... is an
empty list, it waits for every child process it has.

wait then execs into prog....

Options

-r : equivalent to -t 0. Do not
pause: only reap processes that are already dead when wait
is invoked.

-ttimeout : wait for a maximum
of timeout milliseconds. If there still are living processes
among pids... (or among wait's children if
pids... is an empty list), after timeout
milliseconds, they will not be reaped.

-I : loose. If wait times out while
waiting for children to die, it will still
exec into prog.... This is the default.

-i : strict. If wait times out, it
will print an error message and exit 1.